Multiple Building Selection is a feature that has been debated on every StarCraft forum since StarCraft 2's unveiling at BlizzCon last year. Essentially, MBS allows players to select as many buildings as they like, and then form them into a control group--allowing remote training of units en masse. The argument against MBS is relatively straightforward: by allowing players to select multiple buildings at once, Blizzard risks simplifying the strategic balance of the game, to the point that the many pro StarCraft gamers will find it uninteresting.

On the show floor at PAX, I learned that Blizzard will be fielding a new StarCraft II build at its upcoming BlizzCon convention, and that MBS will be changed from the version shown at WWI and PAX.

StarCraft II community manager Kevin "Karune" Yu talked me through the various tweaks.

Shack: Will there be a new build at BlizzCon?

Kevin Yu: Yes, there will be a new build at BlizzCon. This is the build from WWI. A couple things are tweaked--especially the Vespene gas mechanics, those are tweaked a little bit.

Shack: The gas drains really quickly now, it seems.

Kevin Yu: Oh yeah, it does. It empties really quickly. You have to actually spend minerals to replenish the gas. So that creates a little more macro in the sense that--some of the concerns right now from the community is that there's not enough macro. It's like, it's easy to build a big army, but there's no real strategy in terms of resource management. StarCraft 1 has always been about micromanagement and macromanagement. You can have some players who are really awesome tactically on the battlefield, getting the most out of each unit, keeping them alive. And then you have other pro gamers who are awesome at macro. They're not as good as keeping every unit alive, but they can build two to three times more units. So then you might still have a balance in a game where you have a good macro player versus a good micro player.

So when you actually add in more gas to those geysers, it shuts down the geyser for a little bit. So basically you have to move those SCVs back onto minerals if you want to get the most use--otherwise they'll stand there a while until the geyser gets replenished.

Shack: So related to this concern about macro, I know a lot of fans are worried about Multiple Building Selection. Are you still making changes to that system, or is that finalized?

Kevin Yu: In the build that you'll see at BlizzCon it's more of a compromise. Clicking on each of the barracks--let's say you have three barracks. It won't be like you press "M" once and you'll have three marines pop out. You're actually going to have to press "M" three times, which is a little more controlled over what comes out. Because let's say you have a tech lab on one, and on another you have a reactor, so they build different units and such. You can actually have a little more control over that now.

We've tried different things like enable tabbing inbetween each building. Like you click a control group of all your barracks, and you have to tab inbetween each time to press "M." So you have a control group that's 4 for your barracks; 4, M, Tab, M, Tab, M, Tab, M.

We made it one step easier on that. We used to have more control. Honestly, the game still requires a lot of skill and we're not too worried about that. We're really thinking that the game is going to have a lot of things we're not expecting. There's going to be a more tactical dynamic to the game, especially with units being able to move a lot faster. All the races are a lot more mobile than they were in StarCraft 1. With Protoss you warp in your army, you don't have to wait for them to cross the map. You can move your whole entire [Zerg] army with the Nydus Canal. Dropships now are very prevalent in StarCraft 2 for Terrans because they also double up as a medic now. More incentive to have dropships and move your army around.

I mean, we're still interested to see how it's going to play out. Balancing for us--I mean, we've already been doing a lot of it, but it doesn't really start until beta. I mean right now I'll say it's not too bad, considering we don't have 10,000 players playing it right now. But when beta hits, we're going to be constantly involved in that, and honestly a lot of times things change quite a bit in beta. It's not unusual for units to get cut or have lots of mechanics changes.